[ Ref. https://www.youtube.com/watch?v=UiYQ0-iya8I 

Hi Steve,  Unfortunately, many of the whistler tunes are now quite
archaic.  I couldn't identify the melody on the YouTube video.
However, the good news is, if you turn the unit over, you will notice
that there are three small holes in the brass bed plate, situated
around the central winding arbor post).

If you allow the movement to operate, you will see a 1- or 2-digit
number (between 1 and 68) appear in one of those holes.  Stop the
motion of the whistler, by touching the flywheel, so that you can
read that number.  With that number we can identify the melody from
the Griesbaum Whistler tune list.

Most sincerely,

Don Caine - Proprietor, The Music Box Repair Center Unlimited
Lomita, California
http://www.musicboxrepaircenter.com/